Since March 2025, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
The forEach() method of Iterator instances is similar to Array.prototype.forEach(): it executes a provided function once for each element produced by the iterator.
forEach(callbackFn)
callbackFnA function to execute for each element produced by the iterator. Its return value is discarded. The function is called with the following arguments:
forEach() iterates the iterator and invokes the callbackFn function once for each element. Unlike most other iterator helper methods, it does not work with infinite iterators, because it is not lazy.
new Set([1, 2, 3]).values().forEach((v) => console.log(v)); // Logs: // 1 // 2 // 3
This is equivalent to:
for (const v of new Set([1, 2, 3]).values()) {
console.log(v);
}
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| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | Bun | Deno | Node.js | |
forEach |
122117–119 | 122117–119 | 131 | 108103–105 | 18.4 | 122117–119 | 131 | 8178–79 | 18.4 | 26.024.0–25.0 | 122117–119 | 18.4 | 1.1.31 | 1.39 | 22.0.0 |
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Iterator/forEach